Provided is a seat where pumping operation of a lever of the seat not only rotates an output member by inching but also, when a load in the operation direction of the lever is applied to the output side member, rotates it at one stroke in that direction. A seat adjustment device of the seat has a clutch unit (X) provided between the lever and a rotation member of a movement mechanism. The clutch unit (X) has a lever side clutch section (11) which is provided on the input side and controls, through lever operation, transmission/interruption of rotational torque to the output side, a brake side clutch section (12) provided on the output side, which transmits input torque from the lever side clutch section (11) to the output side, and interrupts reverse input torque from the output side, and a rotation control clutch section (13) which is disposed adjacent to the brake side clutch section (12), allows a pinion shaft (28) of the brake side clutch section (12) to rotate by inching through pumping operation where the lever of the lever side clutch section (12) is rotated in one direction, and makes the pinion shaft (28) rotatable through a single operation in which the lever is rotated in the opposite direction.